A human and Autopilot working together is safer than just a human driving. Autopilot by itself is currently less safe than just a human driving (which is why it's still level 2). There's no mixed messaging.
This is not my understanding from colleagues who studied the human factors of what is now called level 2/3 automation many years ago. Partial automation fell into an "uncanny valley" in which the autopilot was good enough most of the time that it lulled most human participants into a false sense of security and caused more (often simulated) accidents than a human driving alone.
Since then I've seen some evidence [1] that with enough experience using an L2 system, operators can increase situational awareness. But overall I wouldn't be surprised if humans with level 2+/3 systems end up causing more fatalities than human operators would alone. That's why I'm relieved to see automakers committing [2] to skipping level 3 entirely.
[1] https://www.iihs.org/api/datastoredocument/bibliography/2220
[2] https://driverless.wonderhowto.com/news/waymo-was-right-why-...
Having worked in the driver monitoring space, it pains me to see a half-baked, black box system like Autopilot deployed without a driver camera. Steering wheel and seat sensors are not up to the task of making sure the driver is attentive. Don't even get me started on "FSD," which proposes to work in harmony with the human driver in far more complex scenarios.
The driver is there just for regulatory purposes, all cars self driving in 2016!, cross country summon in 2017, coast to coast autonomous drive in 2018, Tesla self driving taxis in 2019, FSD making teslas worth 250k$ in 2020! Etc etc
There are a lot of statements by Elon Musk
On the next day: "I'll sell you this box. I know it's empty today, but tomorrow..."
I am not so sure. The data from Tesla is always comparing apples and oranges and I have not seen a good third-party analysis confirming this hypothesis.